Motion compensation in hybrid X-ray/camera interventions

Abstract

A system and method of assisting a treatment procedure is provided, the method comprising the steps of determining a 3-D intervention vector in relation to an inner body structure of a body of interest based on a 3-D x-ray image, determining a 3-D position of an entry point on an outer surface of the body of interest based on the intervention vector, comparing the position and/or orientation of the inner body structure in the 3-D x-ray image with the position and/or orientation of the inner body structure in an additional 2-D x-ray image being generated transverse to the intervention vector, correcting the 3-D position of the entry point on the outer surface of the body of interest based on a deviation detected in the comparing step.

The invention claimed is: 
     
       1. A device for assisting a treatment procedure, comprising:
 an x-ray device with an x-ray source and an x-ray detector, wherein the x-ray device is configured to generate 2-D projection images of a body of interest from different angles relative to the body of interest, 
 a camera, wherein the camera is configured to generate an image with an imaging direction of an outer surface of the body of interest, and wherein the camera is arranged in a predetermined relation to the x-ray device, 
 a processing unit for processing the image data from the x-ray device and the image data from the camera, wherein the processing unit is configured
 to reconstruct a 3-D image of the body of interest based on a plurality of 2-D projection images generated from different angles relative to the body of interest, 
 to determine a direction of an intervention to be performed on an inner body structure, 
 to receive a single 2-D projection image with a projection direction being transverse to the direction of the intervention, 
 to register the single 2-D projection image with the 3-D image, 
 to detect a deviation of a position and/or orientation of an inner body structure as visualized in the virtual projection image from the position and/or orientation of the inner body structure as visualized in the single 2-D projection image, and 
 to indicate in the camera image a position on the outer surface for the intervention to be performed on the inner body structure. 
 
 
     
     
       2. The device of  claim 1 , wherein the processing unit is further configured to identify a region of interest in the 3-D image and to identify a corresponding region of interest in the single 2-D projection image, and wherein the registering of the single 2-D projection image with the 3-D image is limited to the region of interest, the region of interest including the inner body structure. 
     
     
       3. The device of  claim 1 , wherein the processing unit is further configured to detect a deviation of positions and/or orientations of a plurality of inner body structures, and wherein the processing unit is further configured to take into account interrelations between the plurality of inner body structures when determining the position on the outer surface to be indicated in the camera image. 
     
     
       4. The device of  claim 1 , wherein the imaging direction of the camera is alignable to the direction of the intervention. 
     
     
       5. The device of  claim 1 , wherein the x-ray device is a c-arm based x-ray device and wherein the camera is fixedly attached to the x-ray device. 
     
     
       6. The device of  claim 1 , wherein the processing unit is further configured
 to identify in the 3-D image a position of at least one landmark on the outer surface of the body of interest, 
 to identify in the camera image a position of the at least one landmark on the outer surface of the body of interest, 
 wherein the position for an intervention is indicated in the camera image in relation to the position of the at least one landmark. 
 
     
     
       7. The device of  claim 6 , further comprising an element configured to be attached to the outer surface of the body of interest, wherein the at least one landmark is formed by the element. 
     
     
       8. A computer program element executable on the processing unit of the device according to  claim 1 , the computer program element comprising sets of instructions for:
 receiving a plurality of 2-D projection images generated from different angle relative a body of interest, 
 generating a 3-D image of the body of interest based on the plurality of 2-D projection images, 
 receiving a further projection image with a projection direction being transverse to a direction of an intended intervention, 
 registering the further projection image with a specific projection image out of the plurality of 2-D projection images, the specific projection images being acquired under the same projection direction as the projection direction of the further projection image, 
 determining a deviation of an inner body structure in the specific projection image from the inner body structure in the further projection image, 
 receiving a camera image of an outer surface of the body of interest, and 
 indicating in the camera image a position of an entry point on the outer surface for the intended intervention on the inner body structure. 
 
     
     
       9. The computer program element of  claim 8 , further comprising sets of instructions for defining a region of interest including the inner body structure, both in the specific projection image and in the further projection image, wherein the registering is limited to the region of interest. 
     
     
       10. The computer program element of  claim 8 , further comprising sets of instructions for determining in the 3-D image a direction of the intervention of the inner body structure. 
     
     
       11. A method of assisting a treatment procedure, the method comprising the steps of
 determining a 3-D intervention vector in relation to an inner body structure of a body of interest based on a 3-D x-ray image, 
 determining a 3-D position of an entry point on an outer surface of the body of interest based on the intervention vector, 
 comparing the position and/or orientation of the inner body structure in the 3-D x-ray image with the position and/or orientation of the inner body structure in an additional 2-D x-ray image being generated transverse to the intervention vector, 
 correcting the 3-D position of the entry point on the outer surface of the body of interest based on a deviation detected in the comparing step. 
 
     
     
       12. The method of  claim 11 , wherein the method comprises the step of determining a 3-D intervention vector in relation to a plurality of inner body structures of a body of interest based on a 3-D x-ray image, and wherein the step of comparing encompasses positions and/or orientations of the plurality of inner body structures. 
     
     
       13. The method of  claim 11 , wherein the step of comparing the position and/or orientation of at least one of the inner body structure includes an identification of a landmark in both the 3-D x-ray image and the additional 2-D x-ray image. 
     
     
       14. The method of  claim 11 , further comprising the step of providing in a camera image an indication of the entry point on the outer surface of the body of interest. 
     
     
       15. The method of  claim 11 , further comprising the step of aligning an imaging direction of the camera with the 3-D intervention vector.